Prevention of human immunodeficiency virus-1 transmission to the infant through breastfeeding: new developments

Attitudes on breast feeding among persons with HIV who have given birth and their perceptions of coercion during counseling on safe infant feeding practices

Persons with HIV can receive mixed messages about the safety of breastfeeding. We sought to assess if they felt coerced to formula feed when counseled about practices to reduce HIV transmission. Persons with HIV who had given birth were eligible to complete a survey to describe their experiences with infant feeding counseling and if they felt coerced to formula feed. An Iowa Infant Feeding Attitude Scale (IIFAS) assessed attitudes towards breastfeeding. Qualitative analyses were performed on narrative responses. One hundred surveys were collected from sites in Georgia, North Carolina, Pennsylvania, and South Carolina. The mean IIFAS score (n, 85) was 47 (SD 9.2), suggesting relatively favorable attitudes toward breastfeeding. Thirteen persons reported feeling coerced to formula feed. When controlling for choosing to give any breast milk, persons with any college education were more likely to report feeling coerced (aOR 9.8 [95% CI 1.8-52.5]). Qualitative analyses revealed three themes: perceiving breastfeeding as unsafe, engaging in shared decision-making, and resisting advice to formula feed. Persons with HIV desire to be counseled about safe infant feeding practices and have their questions answered without judgement. We highlight experiences of persons with HIV that reflect a need for a nuanced approach to infant feeding counseling.

Human Breast Milk: From Food to Active Immune Response With Disease Protection in Infants and Mothers

Breastfeeding is associated with long-term wellbeing including low risks of infectious diseases and non-communicable diseases such as asthma, cancer, autoimmune diseases and obesity during childhood. In recent years, important advances have been made in understanding the human breast milk (HBM) composition. Breast milk components such as, non-immune and immune cells and bioactive molecules, namely, cytokines/chemokines, lipids, hormones, and enzymes reportedly play many roles in breastfed newborns and in mothers, by diseases protection and shaping the immune system of the newborn. Bioactive components in HBM are also involved in tolerance and appropriate inflammatory response of breastfed infants if necessary. This review summarizes the current literature on the relationship between mother and her infant through breast milk with regard to disease protection. We will shed some light on the mechanisms underlying the roles of breast milk components in the maintenance of health of both child and mother.

Healthcare Workers' Knowledge of HIV-Exposed Infant Feeding Options and Infant Feeding Counseling Practice in Northern Nigeria

BACKGROUND

Despite the existence of evidence-based HIV-exposed infant feeding guidelines, infants in Africa still acquire HIV through inappropriate feeding practices.

OBJECTIVE

To identify predictors of HIV-exposed infant feeding knowledge and counseling practice among health care workers (HCW) in Nigeria.

METHODS

Structured, pretested questionnaires were administered to HCW (n=262) in a tertiary health facility in Kano, Nigeria. Multivariate logistic regression was used to determine predictors of HIV-exposed infant feeding knowledge and counseling practice.

RESULTS

Of 262 respondents, (58.0%, n=152) had good knowledge of recommended feeding options. Respondents listed exclusive breastfeeding (57.6%, n=151), human milk substitutes (45.4%, n=119), HIV-negative wet-nursing (37.0%, n=97), heated expressed human milk (20.6%, n=54) and mixed feeding (13.4%, n=35) as appropriate feeding choices. Over half (57.3%, n=150) of the respondents have ever counseled a HIV-positive mother on infant feeding. Knowledge was predicted by female sex (Adjusted Odds Ratio (AOR)=2.47, 95% Confidence Interval (CI):1.35-4.52), profession (physician vs. laboratory scientist, AOR=4.00, 95%CI:1.25-12.87; nurse/midwife vs. laboratory scientist, AOR=2.75, 95%CI:1.17-9.28), infant feeding counseling training (AOR=3.27, 95%CI:1.87-5.71), and number of children (2-4 vs. 0, AOR=1.75, 95%CI:1.23-3.92). Infant feeding counseling was predicted by female sex (AOR=2.85, 95%CI:1.39-5.85), age (>40 vs. <30 years, AOR=3.87, 95%CI:1.27-15.65), knowledge of infant feeding options (good vs. fair/poor, AOR=3.96, 95%CI:2.07-7.59), training (AOR=2.60, 95%CI:1.42-5.32), and profession (physician vs. laboratory scientist, AOR=10.7, 95%CI:2.85-40.54; nurse/midwife vs. laboratory scientist, AOR=4.8, 95%CI:1.26-18.02).

CONCLUSION

The practice of infant feeding counseling among HCW in Nigeria is associated with sex, knowledge, and profession. Our findings may inform the development of targeted training programs for HCW in similar settings.

Neutralization of HIV subtypes A and D by breast milk IgG from women with HIV infection in Uganda

OBJECTIVES

Among HIV-exposed infants in resource-limited countries, 8-12% are infected postnatally by breastfeeding. However, most of those uninfected at birth remain uninfected over time despite daily exposure to HIV in breast milk. Thus, we assessed the HIV-inhibitory activity of breast milk.

METHODS

We measured cross-clade neutralization in activated PBMC of Ugandan subtype A (92UG031) and D (92UG005) primary HIV by breast milk or purified milk IgG and IgA from 25 HIV-infected Ugandan women. Isotype-specific antigen recognition was resolved by immunoblot. We determined HIV subtype from envelope population sequences in cells from 13 milk samples by PCR.

RESULTS

Milk inhibited p24 production by ≥50% (dose-dependent) by subtype A (21/25; 84%) and subtype D (11/25; 44%). IgG consistently reacted with multiple HIV antigens, including gp120/gp41, but IgA primarily recognized p24 alone. Depletion of IgG (n = 5), not IgA, diminished neutralization (mean 78 ± 33%) that was largely restored by IgG repletion. Mothers infected with subtype A more effectively neutralized subtype A than D.

CONCLUSIONS

Breast milk from HIV-infected women showed homotypic and cross-subtype neutralization of HIV by IgG-dependent and -independent mechanisms. These data direct further investigations into mechanisms of resistance against postnatal transmission of HIV to infants from their mothers.

A phase I randomized clinical trial of candidate human immunodeficiency virus type 1 vaccine MVA.HIVA administered to Gambian infants

BACKGROUND

A vaccine to decrease transmission of human immunodeficiency virus type 1 (HIV-1) during breast-feeding would complement efforts to eliminate infant HIV-1 infection by antiretroviral therapy. Relative to adults, infants have distinct immune development, potentially high-risk of transmission when exposed to HIV-1 and rapid progression to AIDS when infected. To date, there have been only three published HIV-1 vaccine trials in infants.

TRIAL DESIGN

We conducted a randomized phase I clinical trial PedVacc 001 assessing the feasibility, safety and immunogenicity of a single dose of candidate vaccine MVA.HIVA administered intramuscularly to 20-week-old infants born to HIV-1-negative mothers in The Gambia.

METHODS

Infants were followed to 9 months of age with assessment of safety, immunogenicity and interference with Expanded Program on Immunization (EPI) vaccines. The trial is the first stage of developing more complex prime-boost vaccination strategies against breast milk transmission of HIV-1.

RESULTS

From March to October 2010, 48 infants (24 vaccine and 24 no-treatment) were enrolled with 100% retention. The MVA.HIVA vaccine was safe with no difference in adverse events between vaccinees and untreated infants. Two vaccine recipients (9%) and no controls had positive ex vivo interferon-γ ELISPOT assay responses. Antibody levels elicited to the EPI vaccines, which included diphtheria, tetanus, whole-cell pertussis, hepatitis B virus, Haemophilus influenzae type b and oral poliovirus, reached protective levels for the vast majority and were similar between the two arms.

CONCLUSIONS

A single low-dose of MVA.HIVA administered to 20-week-old infants in The Gambia was found to be safe and without interference with the induction of protective antibody levels by EPI vaccines, but did not alone induce sufficient HIV-1-specific responses. These data support the use of MVA carrying other transgenes as a boosting vector within more complex prime-boost vaccine strategies against transmission of HIV-1 and/or other infections in this age group.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00982579. The Pan African Clinical Trials Registry PACTR2008120000904116.

Feasibility and safety of ALVAC-HIV vCP1521 vaccine in HIV-exposed infants in Uganda: results from the first HIV vaccine trial in infants in Africa

BACKGROUND

The development of a safe and effective vaccine against HIV type 1 for the prevention of mother-to-child transmission of HIV would significantly advance the goal of eliminating HIV infection in children. Safety and feasibility results from phase 1, randomized, double-blind, placebo-controlled trial of ALVAC-HIV vCP1521 in infants born to HIV type 1-infected women in Uganda are reported.

METHODS

HIV-exposed infants were enrolled at birth and randomized (4:1) to receive vaccine or saline placebo intramuscular injections at birth, 4, 8, and 12 weeks of age. Vaccine reactogenicity was assessed at vaccination and days 1 and 2 postvaccination. Infants were followed until 24 months of age. HIV infection status was determined by HIV DNA polymerase chain reaction.

RESULTS

From October 2006 to May 2007, 60 infants (48 vaccine and 12 placebo) were enrolled with 98% retention at 24 months. One infant was withdrawn, but there were no missed visits or vaccinations among the 59 infants retained. Immune responses elicited by diphtheria, polio, hepatitis B, haemophilus influenzae type B, and measles vaccination were similar in the 2 arms. The vaccine was well tolerated with no severe or life-threatening reactogenicity events. Adverse events were equally distributed across both study arms. Four infants were diagnosed as HIV infected [3 at birth (2 vaccine and 1 placebo) and 1 in vaccine arm at 2 weeks of age].

CONCLUSION

The ALVAC-HIV vCP1521 vaccination was feasible and safe in infants born to HIV-infected women in Uganda. The conduct of high-quality infant HIV vaccine trials is achievable in Africa.

The prevention of mother-to-child transmission of HIV: are we translating scientific success into programmatic failure?

PURPOSE OF REVIEW

The prevention of mother-to-child transmission of HIV stands as one of the first and most successful applications of scientific enquiry in the AIDS epidemic. While paediatric HIV has virtually been eliminated in industrialized countries, nearly 500 000 children were infected worldwide in 2007. This review considers the global successes and failures of prevention of mother-to-child transmission in order to shed light on the key question: why have relevant research advances not yet been successfully implemented in low-resource settings?

RECENT FINDINGS

This review examines the accumulated evidence that has led to the definition of prevention strategies, and corresponding prevention of mother-to-child transmission guidelines. Numerous field implementation reports, in contrast, point to the global lack of success of prevention of mother-to-child transmission programmes and pinpoint key factors which continue to drive their failure, including the low uptake of HIV counselling and testing, continuing postnatal transmission through breastfeeding, and the lack of linkages between prevention of mother-to-child transmission programmes and primary prevention, family planning and, most importantly, the provision of care and treatment.

SUMMARY

Two country examples, Thailand and South Africa, illustrate that political will is the most important factor for the success of prevention of mother-to-child transmission interventions. Much more needs to be done to translate the remarkable prevention of mother-to-child transmission research progress into programme success.

The human milk microbiota: origin and potential roles in health and disease

Human milk has been traditionally considered sterile; however, recent studies have shown that it represents a continuous supply of commensal, mutualistic and/or potentially probiotic bacteria to the infant gut. Culture-dependent and -independent techniques have revealed the dominance of staphylococci, streptococci, lactic acid bacteria and bifidobacteria in this biological fluid, and their role on the colonization of the infant gut. These bacteria could protect the infant against infections and contribute to the maturation of the immune system, among other functions. Different studies suggest that some bacteria present in the maternal gut could reach the mammary gland during late pregnancy and lactation through a mechanism involving gut monocytes. Thus, modulation of maternal gut microbiota during pregnancy and lactation could have a direct effect on infant health. On the other hand, mammary dysbiosis may lead to mastitis, a condition that represents the first medical cause for undesired weaning. Selected strains isolated from breast milk can be good candidates for use as probiotics. In this review, their potential uses for the treatment of mastitis and to inhibit mother-to-infant transfer of HIV are discussed.

Infant feeding practice and associated factors of HIV positive mothers attending prevention of mother to child transmission and antiretroviral therapy clinics in Gondar Town health institutions, Northwest Ethiopia

Background

It has been estimated that 430,000 children under 15 years of age were newly infected with HIV in 2008, and more than 71% are living in sub-Saharan Africa. In the absence of intervention to prevent mother-to-child transmission, 30-45% of infants born to HIV-positive mothers in developing countries become infected during pregnancy, delivery and breastfeeding. The aim of this study was to assess infant feeding practice and associated factors of HIV positive mothers attending prevention of mother to child transmission and antiretroviral therapy clinics of Northwest Ethiopia.

Methods

Institution based cross sectional study was conducted from January to May 2011 among all HIV positive mothers with less than two years old child attending prevention of mother to child transmission and antiretroviral therapy clinics in Gondar Town health institutions. A structured pre-tested questionnaire using interview technique was used for data collection. The data was entered and analyzed using SPSS version 16 statistical package.

Results

A total of 209 HIV positive mothers were included in the study. Of these, 187 (89.5%) had followed the recommended way of infant feeding practice while significant percentage (10.5%) had practiced mixed breast feeding. In multivariate analysis, disclosure of HIV status with their spouse, insufficient breast milk and occupational status were found to be independently associated (p-value of < 0.05) with recommended infant feeding practice. Lack of resource, stigma of HIV/AIDS, and husband opposition were also obtained as factors that influenced choice of infant feeding options by respondents.

Conclusions

Higher proportion of respondents used the recommended way of infant feeding practice by WHO as well as by Ethiopian Ministry of Health. However, mixed feeding in the first 6 months of age, an undesirable practice in infant feeding, were reported in this study. Infant feeding education that is aligned to national policy should be strengthened in primary health care, particularly in situations where prevention of mother to child transmission of HIV is prioritized.

Host factors that influence mother-to-child transmission of HIV-1: genetics, coinfections, behavior and nutrition

Mother-to-child transmission (MTCT) is the most important mode of HIV-1 acquisition among infants and children and it can occur in utero, intrapartum and postnatally through breastfeeding. Great progress has been made in preventing MTCT through use of antiretroviral regimens during gestation, labor/delivery and breastfeeding. The mechanisms of MTCT, however, are multifactorial and remain incompletely understood. This review focuses on select host factors affecting MTCT, in particular genetic factors, coexisting infections, behavioral factors and nutrition. Whereas much emphasis has been placed on decreasing maternal HIV-1 viral load, an important determinant of MTCT, through use of antiretroviral agents, complementary focus on overall maternal health is often neglected. By addressing coinfections in mothers and infants, improving the mother's nutritional status and modifying risky behaviors and practices, not only is maternal and child health improved, but a direct benefit in reducing MTCT can be derived. The study of genetic variations in susceptibility to HIV-1 infection is rapidly evolving, and the future is likely to bring revolutionary changes in HIV-1 prevention by enhancing natural resistance to infection and by individually tailoring pharmacologic regimens.

Perinatal HIV and its prevention: progress toward an HIV-free generation

This article reviews the epidemiology of perinatal (HIV)-1 in the United States in the past 2 decades and the international HIV epidemic among pregnant women and their infants. Since the peak of 1700 reported cases of pediatric AIDS in 1992, there has been dramatic progress in decreasing perinatal HIV transmission in the United States with fewer than 50 new cases of AIDS annually (>96% reduction) and fewer than 300 annual perinatal HIV transmissions in 2005. This success has been due to use of combination antiretrovirals given to mothers during pregnancy and labor/delivery, obstetric interventions that reduce the risk of transmission, provision of zidovudine (ZDV) prophylaxis for 6 weeks to HIV-exposed newborns and use of formula. Internationally, the burden of mother-to-child HIV transmission remains heavy with 2.1 million children less than 15 years of age estimated to be living with HIV and 430,000 new HIV infections in infants occurring each year, with most cases occurring in Africa. Current international efforts are directed at scaling up successful prevention of mother-to-child transmission interventions and new research directed at making breastfeeding safer using antiretroviral prophylaxis to either mothers or their infants.

HIV-1 and breastfeeding: biology of transmission and advances in prevention

Breastfeeding accounts for about 40% of mother-to-child transmission of HIV-1 worldwide and carries an estimated risk of transmission of 0.9% per month after the first month of breastfeeding. It is recommended that HIV-1-infected women completely avoid breastfeeding in settings where safe feeding alternatives exist. However, as replacement feeding is not safely available in many parts of the world, and because breastfeeding provides optimal nutrition and protection against other infant infections, there is intense ongoing research to make breastfeeding safe for HIV-1-infected mothers in resource-limited settings. More research is needed to determine the optimal duration of breastfeeding, optimal weaning practices, and which individual antiretroviral prophylactic regimen is best for HIV-1-infected mothers and their infants in a particular setting.

Eighteen-month follow-up of HIV-1-infected mothers and their children enrolled in the Kesho Bora study observational cohorts

OBJECTIVE

To assess the effectiveness and safety of antiretrovirals (ARVs) used for treatment or prophylaxis in a breastfeeding population of HIV-1-infected women (Burkina-Faso, Kenya, South Africa).

METHODS

HIV-1-infected pregnant women with <200 CD4 cells per cubic millimeter or with World Health Organization stage 4 disease (cohort A) and asymptomatic women with >500 CD4 cells per cubic millimeter (cohort B) were enrolled into 2 prospective cohorts. Women with 200-500 CD4 cells per cubic millimeter were enrolled in a parallel randomized trial. Women in cohort A initiated antiretroviral therapy. Women in cohort B received zidovudine from 34 to 36 weeks gestation until delivery, with single-dose nevirapine in labor (cohort B). All children received single-dose nevirapine.

RESULTS

Of 248 women enrolled, 111 (cohort A) and 125 (cohort B) infants alive at 24 hours after birth were analyzed. Sixty-nine percent and 42% of women had undetectable viral load at delivery, respectively. Ten children in each cohort died. The 18-month cumulative incidences of HIV-1 infection were 7.5% (95% confidence interval: 3.8% to 14.5%) (cohort A) and 5.8% (2.8% to 11.8%) (cohort B). Sixty-one percent (cohort A) and 78% (cohort B) were breastfed for a median duration of 20 weeks. Four children in cohort A and only 1 in cohort B became HIV-1 infected after 6 weeks of age.

CONCLUSIONS

Antiretroviral therapy initiated a median of 7 weeks before delivery in women with advanced HIV-1 disease was associated with a significant residual risk of HIV-1 transmission due to insufficient decrease in viral load by the time of delivery. Among women with >500 CD4 cells per cubic millimeter, the risk of breast-milk transmission was very low despite lack of postnatal prophylaxis.

Inhibition of human immunodeficiency virus type 1 by lactic acid bacteria from human breastmilk

BACKGROUND

Human breastmilk provides a rich source of commensal lactic acid bacteria (LAB) to the infant during breastfeeding and stimulates abundant growth and colonization of these bacteria at mucosal surfaces in the infant gastrointestinal tract. While conferring critical nutritional and immunologic support to the developing newborn, breastmilk also serves as a vehicle for human immunodeficiency virus type 1 (HIV-1) transmission from mother to child during breastfeeding. Whether breastmilk LAB confer protection against mucosal exposure to HIV-1 in breastfeeding infants is unknown.

STUDY DESIGN

In the present study, we sought to evaluate LAB isolated from the breastmilk of healthy women for the ability to inhibit HIV-1 infection in vitro. A total of 38 strains of breastmilk bacteria were evaluated in this study. Both heat-killed bacteria and cell-free conditioned supernatants from bacterial cultures were tested for the ability to inhibit infection with HIV-1 using viral isolates with tropism for CCR5 (R5), CXCR4 (X4), or R5/X4 dual-tropism.

RESULTS

Significant inhibition of R5-tropic HIV-1 was demonstrated using heat-killed bacteria, most notably among breastmilk strains of Lactobacillus and Pediococcus. Selected strains of breastmilk LAB also demonstrated significant inhibition of HIV-1 infection against virus with tropism for X4 and R5/X4.

CONCLUSION

These results demonstrate for the first time that commensal LAB from human breastmilk inhibit HIV-1 infection in vitro and suggest a possible role for these bacteria in mucosal protection against HIV-1 in the breastfeeding infant.

Infectious disease and reproductive health: a review

Human reproduction provides unique opportunities for the transmission of infectious agents. Furthermore, the mother and her offspring have distinct susceptibilities to infection at each stage of reproduction, from conception and gestation to parturition and the neonatal period. The impact of pathogens on reproduction can be mitigated or exacerbated depending on timing of acquisition during pregnancy. Similarly, factors such as maternal immune response, nutritional status, or concurrent infection may modify the effect of an infectious agent. In this review, we discuss the evidence--or lack thereof--for associations between infectious agents and reproductive problems at each stage of reproduction. We focus on well-substantiated associations, and consider several emerging or controversial associations. We discuss the challenges, limitations, and opportunities related to epidemiologic research on infectious disease and reproductive outcomes.

TARGET AUDIENCE

Obstetricians & Gynecologists, Family Physicians.

LEARNING OBJECTIVES

After completion of this article, the reader will be able to describe the potential mechanisms by which infectious agents may impact productive health, explain the public health impact of infectious diseases on reproductive health, and summarize the perinatal risks of infectious disease and relate this to treatment and prevention strategies in practice.

Lower risk of resistance after short-course HAART compared with zidovudine/single-dose nevirapine used for prevention of HIV-1 mother-to-child transmission

BACKGROUND

Antiretroviral resistance after short-course regimens used to prevent mother-to-child transmission has consequences for later treatment. Directly comparing the prevalence of resistance after short-course regimens of highly active antiretroviral therapy (HAART) and zidovudine plus single-dose nevirapine (ZDV/sdNVP) will provide critical information when assessing the relative merits of these antiretroviral interventions.

METHODS

In a clinical trial in Kenya, pregnant women were randomized to receive either ZDV/sdNVP or a short-course of HAART through 6 months of breastfeeding. Plasma samples were collected 3-12 months after treatment cessation, and resistance to reverse transcriptase inhibitors was assessed using both a sequencing assay and highly sensitive allele-specific polymerase chain reaction assays.

RESULTS

No mutations associated with resistance were detectable by sequencing in either the ZDV/sdNVP or HAART arms at 3 months posttreatment, indicating that resistant viruses were not present in >20% of virus. Using allele-specific polymerase chain reaction assays for K103N and Y181C, we detected low levels of resistant virus in 75% of women treated with ZDV/sdNVP and only 18% of women treated with HAART (P = 0.007). Y181C was more prevalent than K103N at 3 months and showed little evidence of decay by 12 months.

CONCLUSIONS

Our finding provides evidence that compared with ZDV/sdNVP, HAART reduces but does not eliminate nevirapine resistance.

An update on HIV and infant feeding issues in developed and developing countries

The field of mother to child transmission of human-immunodeficiency virus is rapidly evolving. In the United States, prevention focuses on implementation of universal human-immunodeficiency virus testing to assure compliance with recommended treatment regimens and infant-feeding strategies. In most cases, this is the avoidance of all breastfeeding. In developing countries, avoidance of breastfeeding places infants at higher risk of morbidity and mortality. Current World Health Organization recommendations require individualized counseling to determine the best feeding method for each woman.

MUC1 in human milk blocks transmission of human immunodeficiency virus from dendritic cells to T cells

Mother-to-child transmission of human immunodeficiency virus-1 (HIV-1) occurs frequently via breast-feeding. HIV-1 targets DC-SIGN+ dendritic cells (DCs) in mucosal areas that allow efficient transmission of the virus to T cells. Here, we demonstrate that the epithelial mucin MUC1, abundant in milk, efficiently bound to DC-SIGN on DC. The O-linked glycans within the mucin domain contained Lewis X structures, that were specifically recognized by the receptor. Interestingly, MUC1 prevented DC-SIGN-mediated transmission of HIV-1 from DCs to CD4+ T cells. We hypothesize that repetitive units of Lewis X, within the mucin domain, play an important role in inhibiting transmission of HIV-1 from mother to child.

Breastfeeding and AIDS in the developing world

PURPOSE OF REVIEW

In developing countries where replacement feeding is generally not feasible or safe, hundreds of thousands of infants acquire HIV infection during breastfeeding. Data from recently completed studies provide insight into the safety and hazards of different feeding approaches as well as the use of antiretroviral therapy to prevent postnatal transmission.

RECENT FINDINGS

Several studies confirm that the benefits of avoiding or shortening breastfeeding are offset by adverse outcomes in those infants who escape infection. Reductions in HIV transmission achieved with either formula feeding or early weaning are counterbalanced by increases in uninfected child mortality resulting in no net benefit for HIV-free survival. However, exclusive breastfeeding is associated with a significant decrease in HIV transmission risk. Antiretroviral treatment during breastfeeding to the mother or her infant appears to reduce the risk of postnatal transmission. Studies evaluating daily nevirapine to the breastfeeding infant suggest protection during the period of treatment. Similarly, infants born to breastfeeding women receiving antiretroviral therapy are at lower risk of acquiring HIV.

SUMMARY

While awaiting further studies defining optimal approaches to preventing HIV transmission during breastfeeding, promoting exclusive breastfeeding and assuring antiretroviral treatment for women with advanced HIV disease will likely prevent the majority of needless maternal and infant deaths.

Determinants of infant growth in Eastern Uganda: a community-based cross-sectional study

BACKGROUND

Child under-nutrition is a leading factor underlying child mortality and morbidity in Sub-Saharan Africa. Several studies from Uganda have reported impaired growth, but there have been few if any community-based infant anthropometric studies from Eastern Uganda. The aim of this study was to describe current infant growth patterns using WHO Child Growth Standards and to determine the extent to which these patterns are associated with infant feeding practices, equity dimensions, morbidity and use of primary health care for the infants.

METHODS

A cross-sectional survey of infant feeding practices, socio-economic characteristics and anthropometric measurements was conducted in Mbale District, Eastern Uganda in 2003; 723 mother-infant (0-11 months) pairs were analysed. Infant anthropometric status was assessed using z-scores for weight-for-length (WLZ), length-for-age (LAZ) and weight-for-age (WAZ). Dependent dichotomous variables were constructed using WLZ < -2 (wasting) and LAZ < -2 (stunting) as cut-off values. A conceptual hierarchical framework was used as the basis for controlling for the explanatory factors in multivariate analysis. Household wealth was assessed using principal components analysis.

RESULTS

The prevalences of wasting and stunting were 4.2% and 16.7%, respectively. Diarrhoea during the previous 14 days was associated with wasting in the crude analysis, but no factors were significantly associated with wasting in the adjusted analysis. The adjusted analysis for stunting showed associations with age and gender. Stunting was more prevalent among boys than girls, 58.7% versus 41.3%. Having brothers and/or sisters was a protective factor against stunting (OR 0.4, 95% CI 0.2-0.8), but replacement or mixed feeding was not (OR 2.7, 95% CI 1.0-7.1). Lowest household wealth was the most prominent factor associated with stunting with a more than three-fold increase in odds ratio (OR 3.5, 95% CI 1.6-7.8). This pattern was also seen when the mean LAZ was investigated across household wealth categories: the adjusted mean difference between the top and the bottom wealth categories was 0.58 z-scores, p < 0.001. Those who had received pre-lacteal feeds had lower adjusted mean WLZ than those who had not: difference 0.20 z-scores, p = 0.023.

CONCLUSION

Sub-optimal infant feeding practices after birth, poor household wealth, age, gender and family size were associated with growth among Ugandan infants.

Improving outcomes in infants of HIV-infected women in a developing country setting

Background

Since 1999 GHESKIO, a large voluntary counseling and HIV testing center in Port-au-Prince, Haiti, has had an ongoing collaboration with the Haitian Ministry of Health to reduce the rate of mother to child HIV transmission. There are limited data on the ability to administer complex regimens for reducing mother to child transmission and on risk factors for continued transmission and infant mortality within programmatic settings in developing countries.

Methods and Findings

We analyzed data from 551 infants born to HIV-infected mothers seen at GHESKIO, between 1999 and 2005. HIV-infected mothers and their infants were given “short-course” monotherapy with antiretrovirals for prophylaxis; and, since 2003, highly active antiretroviral therapy (HAART) when clinical or laboratory indications were met. Infected women seen in the pre-treatment era had 27% transmission rates, falling to 10% in this cohort of 551 infants, and to only 1.9% in infants of women on HAART. Mortality rate after HAART introduction (0.12 per year of follow-up [0.08–0.16]) was significantly lower than the period before the availability of such therapy (0.23 [0.16–0.30], P<0.0001). The effects of maternal health, infant feeding, completeness of prophylaxis, and birth weight on mortality and transmission were determined using univariate and multivariate analysis. Infant HIV-1 infection and low birth weight were associated with infant mortality in less than 15 month olds in multivariate analysis.

Conclusions

Our findings demonstrate success in prevention of mother-to-child HIV transmission and mortality in a highly resource constrained setting. Elements contributing to programmatic success include provision of HAART in the context of a comprehensive program with pre and postnatal care for both mother and infant.

Persistence of nevirapine in breast milk and plasma of mothers and their children after single-dose administration

OBJECTIVES

Nevirapine is widely used in the developing world for the prevention of mother-to-child transmission (PMTCT) of HIV. A single mutation in the HIV genome is sufficient to lead to significant nevirapine resistance. Persistence of low-level drug concentrations in body compartments can foster resistance formation. In this study, concentration-time courses of nevirapine after single-dose administration were analysed over an extended post-partum period.

PATIENTS AND METHODS

Breast milk and plasma samples of 62 HIV-positive Ugandan mother-child pairs who had received single-dose nevirapine were collected at delivery and 1, 2 and 6 weeks post-partum. Nevirapine concentrations were quantified by LC/tandem-mass-spectrometry using a quantification limit of 15 ng/mL, and a population pharmacokinetic (PK) analysis was performed.

RESULTS

Concentration-time profiles in breast milk, maternal plasma and child plasma showed similar shapes. At week 1, median nevirapine concentrations were 164 ng/mL in maternal plasma, 114 ng/mL in breast milk and 183 ng/mL in child plasma. The population PK model predicted nevirapine concentrations>10 ng/mL (IC50 for nevirapine) for 13 days in breast milk, 14 days in maternal plasma and 18 days in child plasma in 80% of the samples.

CONCLUSIONS

Nevirapine concentrations were present for 2-3 weeks in the three compartments. The concentrations are probably sufficiently high to protect most breastfed children from HIV transmission during the first 2 weeks. The long presence of slowly decreasing levels of nevirapine is likely to induce resistance formation. Post-natal addition of antiretrovirals for 1 week only, as recommended in the current PMTCT guidelines, will not suffice to avoid nevirapine resistance formation.

Analysis of nevirapine (NVP) resistance in Ugandan infants who were HIV infected despite receiving single-Dose (SD) NVP versus SD NVP plus daily NVP up to 6 weeks of age to prevent HIV vertical transmission

BACKGROUND

Single-dose nevirapine (SD NVP) at birth plus NVP prophylaxis for the infant up to 6 weeks of age is superior to SD NVP alone for prevention of vertical transmission of human immunodeficiency virus (HIV) through breastfeeding. We analyzed NVP resistance in HIV-infected Ugandan infants who received either SD NVP or extended NVP prophylaxis.

METHODS

We tested plasma HIV by using a genotyping assay (ViroSeq; Celera Diagnostics), a phenotypic resistance assay (PhenoSense; Monogram Biosciences), and sensitive point mutation assay (LigAmp, for K103N, Y181C, and G190A).

RESULTS

When infants were 6 weeks old, ViroSeq detected NVP resistance in a higher proportion of infants in the extended NVP arm than in the SD NVP arm (21 of 25 [84%] vs. 12 of 24 [50%]; P = .01). Similar results were obtained with LigAmp and PhenoSense. In both study arms, infants who were HIV infected at birth frequently had NVP resistance detected. In contrast, infants in the extended NVP arm who were HIV infected after birth were more likely to have resistance detected at 6 weeks, compared with infants in the SD NVP arm. The use of extended NVP prophylaxis was also associated with detection of NVP resistance by ViroSeq at 6 months (7 of 7 [100%] infants in the extended NVP arm had resistance detected, compared with 1 of 6 [16.7%] infants in the SD NVP arm; P = .005).

CONCLUSIONS

The use of extended NVP prophylaxis was associated with increased selection for and persistence of NVP resistance in HIV-infected Ugandan infants.

Modifications of a large HIV prevention clinical trial to fit changing realities: a case study of the Breastfeeding, Antiretroviral, and Nutrition (BAN) protocol in Lilongwe, Malawi

In order to evaluate strategies to reduce HIV transmission through breast milk and optimize both maternal and infant health among HIV-infected women and their infants, we designed and implemented a large, randomized clinical trial in Lilongwe, Malawi. The development of protocols for large, randomized clinical trials is a complicated and lengthy process often requiring alterations to the original research design. Many factors lead to delays and changes, including study site-specific priorities, new scientific information becoming available, the involvement of national and international human subject committees and monitoring boards, and alterations in medical practice and guidance at local, national, and international levels. When planning and implementing a clinical study in a resource-limited setting, additional factors must be taken into account, including local customs and program needs, language and socio-cultural barriers, high background rates of malnutrition and endemic diseases, extreme poverty, lack of personnel, and limited infrastructure. Investigators must be prepared to modify the protocol as necessary in order to ensure participant safety and successful implementation of study procedures. This paper describes the process of designing, implementing, and subsequently modifying the Breastfeeding, Antiretrovirals, and Nutrition, (BAN) Study, a large, on-going, randomized breastfeeding intervention trial of HIV-infected women and their infants conducted at a single-site in Lilongwe, Malawi. We highlight some of the successes, challenges, and lessons learned at different stages during the conduct of the trial.

Infections related to pregnancy

Infections in pregnancy and in the postpartum period represent an important knowledge base that emergency physicians should have. Being able to understand the risk that pregnancy-related infections have on maternal and fetal health in addition to the initiation of appropriate treatment for these infections is crucial. In the postpartum period, most infections (94%) are likely to manifest after hospital discharge; therefore, patients frequently present to the emergency department.

Infant feeding and prevention of mother-to-child transmission of HIV-1

PURPOSE OF REVIEW

To review new studies and directions regarding infant feeding and HIV-1 transmission.

RECENT FINDINGS

With antiretroviral drugs and shortened breastfeeding, breast milk HIV-1 transmission risk can be decreased from 16 to less than 5%. In the context of peripartum antiretroviral drugs/short breastfeeding, replacement feeding provides negligible benefit in decreasing the risk of HIV-1/death in contrast to previous studies of no antiretroviral drugs/unlimited breastfeeding in which it offered benefit. One study noted a high risk of infant HIV-1 or death (>/=17%) after 4 months, with no difference in risk in infants with shortened breastfeeding versus indefinite breastfeeding. This study suggests that shortened breastfeeding needs caution in implementation. Other African studies have noted minimal risk of HIV-1 or death (< 2%) after shortened breastfeeding, underscoring the heterogeneity of infant survival in different settings and the potential to improve infant survival.

SUMMARY

Antiretroviral drugs and shortened breastfeeding markedly decrease breastfeeding HIV-1 transmission, shifting the balance to make replacement feeding less beneficial. In some settings shortened breastfeeding poses similar risks as replacement feeding and provides no infant health benefit compared with extended breastfeeding. Programmes aimed at decreasing infant HIV-1 need to do so in the context of promoting infant survival. Strengthening systems to promote infant health is critical.